Paraffin scraper



Filed 001;. 20, 1937 a M m PW v a u. H w m 5 g.

l l HM l l HMWW 4 III F M a Patented Sept. 13, 1938 UNITED STATES PATENTOFFICE] Mllam A. Cowen, Gladewater, Tex assignor of one-fourth to EdwardRasnek, Kllgore, Tex.

Application October 20, 1937, Serial No. 110,111 2 Claims. (011. 166-48)The invention relates to an oil well tool, and

manner eliminating any. scraping action upon the inner surface of thecasing or tube during downward stroke and on the reverse stroke orupward movement of the stem the blades will automatically move to aposition for complete scraping action on the inner surface of the easingor tube for the removal of paraflin or other accumulated substancetherefrom which createsobstruction to the free flow of oil from the 20well in the pumping thereof.

Another object of the invention is the provision of a device of thischaracter, wherein the mounting and working of the blades arenovel,being self-adjustablefor positive scraping optr'oduced into a, wellcasing or tube.

A further object of the invention is the provision of a device of thischaracter, wherein the blades are assisted downwardly in a well cas- 0'ing or tube through the medium of a weight located beneath the saidblades in their fitting with carrier or stem therefor and in thisdownward movement the said blades are inactive for scraping operation.

provision of a device of this character, which is simple inconstruction, thoroughly reliable and efiicient in operation, strong,durable, automatically adjustable from scraping to non-scrapingpositions during operation thereof, and inexpensive to manufacture.

With these .and other objects in view the invention consists in thefeatures of construction, combination and arrangement of parts as willbe hereinafter more fully described, illustrated in the accompanyingdrawing, which discloses the preferred embodiment of the invention, andpointed out in the claims'hereunto appended.

In the accompanying drawing: I

Figure 1 is an elevation of the device constructed in accordance withthe invention and shown in scraping position within an oil well casing,the latter being in vertical section.

Figure 2 is a side elevation of the device reeration in the working ofthe device when in- A still further object of the invention is the movedfrom the casing, being partly. in section.

Figure 3 is a sectional view taken on the line 3-3 'of Figure 4 lookingin the direction of the arrows.

Figure 4 is a sectional view on an enlarged scale'taken on the line 4-4of Figure 2.

Figure 5 is a sectional view on the line 55 of Figure 2.

Similar reference characters indicate corresponding parts throughout theseveral views in the drawing.

Referring to the drawingin detail A designates generally a portion of anoil well casing or tube and B the scraping device, respectively, whichlatter constitutes the present invention and will be hereinafter fullydescribed. v

The device B comprises a stem or shank It). having a major lower portionll downwardly tapered and a minor ,upper portion l2 reversely tapered,while between these portions is a cupshaped holder forming a'carrier l3,being exteriorly formed on the stem or shank ill. This carrier l3between its side wall It which is upwardly flared and the outer surfaceadjacent thereto of the stem or shank It forms an annular downwardlydirected wedge-shape seat l5 for a plurality of sector or segment shapedscraper blades it, these being downwardly tapered in a longitudinaldirection or reversely to the minor portion i2 of the stem or shank it.The blades H5 at their narrower ends are adapted for seating and wedgeengagement in the seat i5 which is the scraping position for said bladeson the upward stroke or movement of the stem or shank .lll.

Concentrically about the minor portion I2 and extending from within thecarrier l3 to a spacing spider or ring H and following the taper of saidportion i2 is a series of uniformly spaced guide rods !8 which arepassed through suitable clearances or passages therefor provided in saidblades 56 and-in this manner the latter are guided toward and away fromthe said carrier pllng with a tool line or a sucker rod (not shown) Therods 88 are removably engaged with the spider or ring it. when the sameis detached from the end 19 ofthe stem or shank l0, and in this mannerthe blades i6 can be pulled oil of the The lower end 2| of the stem orshank. Ill is said rods i8, the latter being welded or otherwise securedto the carrier l3 interiorly thereof.

' II of the stem or shank effects weight below the 'blades Hi to assistin the lowering of the device exteriorly threaded for fastening to acoupling box (not shown) of the line or sucker rodand this box togetherwith the lower major portion cross-sectional sizes or diameters of tubesor casings. When the said blades are in scraping position they will haveclose contact with the,

inner surface of the casing or tube A and such blades at their largerends are of greater circular diameter than the open end of the carrierit. When the blades l6 move away from the carrierl3 on the down strokeof the stem or shank 56- they will not scrape the inner surface of thecasing or tube A, the device being lowered into the latter and duringthis movement the blades are in nonscraping position, while on theupstroke of the device the said blades [6 move to scraping position.

The upstroke of the device removes paraffin or the like 24 from theinner surface of the casing or tube A for the free flow of oil from thewell during the pumping operation.

What is claimed is:

l. A device of the character described, comprising a stem having anupwardly tapered minor portion, a cup-shaped carrier located at thetapered minor portion, and shiftable sector shaped blades about the saidminor portion and reversely tapered thereto for seating and unseating inand from the carrier. g

2. A device of the character described, comprising a stem having atapered portion, a plurality of sector shaped scraper blades around saidtapered portion, a cup shaped receiver for the blades, and means forguiding the blades into and from the receiver.

MILAM A. COWEN'.

